Untargeted Metabolomics Analysis of Serum Metabolites in Zucker Diabetic Fatty Rats

Zucker Diabtic Fatty rats is a common model used for the studies related to type 2 diabetes. Metabolomics, proven by previous studies, can be used for the prediction of phenotype. This investigation held untargeted metabolomics analysis on the serum metabolites of the Zucker Diabetic Fatty rats, intended to gain insights in the study of the pathology of type 2 diabetes. LCMS method (liquid chromatography coupled with mass spectrometry) is an analytical chemistry technique used to separate and purify complex mixtures. After identifying metabolites using MS2 library spectrum matching, this investigation used Metabo Analyst to compare fatty rats and lean rats. Lastly, by applying over representation analysis, we identified seven metabolic pathways that are important for humans, which assists in discovery of therapeutic targets and the developments of diabetes biomarkers.

Characterization of odorous compounds from bleached kraft pulp mill effluent

Odour compounds in extracts of bleached kraft pulp mill effluent (BKME) have been characterized by olfactory gas chromatography (OGC) and gas chromatography-mass spectrometry. A variety of sulfury odours was detected by OGC in addition to woody and pulp mill-like odours. Three sulfur compounds were identified by comparison of retention times and partial mass spectra with authentic standards: dimethyl disulfide, 3-methylthiophene and thioanisole (methyl phenyl sulfide). Typical concentrations in BKME were 1, 0.05, and 0.5 μg/l, respectively. Their odour intensity is relatively low and they were not detected by OGC. Dimethyl trisulfide was tentatively identified by comparison of its partial mass spectrum with a literature (library) spectrum. Its concentration in BKME was estimated at 0.5-2 μg/l. It corresponded to a skunky odour in the OGC profiles. Efforts to identify another odour peak, eluting just after 3-methylthiophene, with a pronounced alkyl sulfide odour were unsuccessful.